I have heard that some of the N9's did shipped a diff headsets other than WH901. As for the WH250 I have read bad review for them. They break easily.
Also for the samsung galaxy headsets are they compatible at all with the N9? The N9 does not have the standard connectors at all so not just any 3.5 jack will work with them. I recently bought a puregear purebeats univ 3.5 jack and it did not work. I think the N9 is using a diff configuration on their 3.5, TRRS I think because it does video transfer as well as an output. You just need to buy the cables for it.